Field of the Invention
The present invention relates to a liquid collection system for use in an evaporative cooler and in particular relates to a drainage collection system for receiving water gravitating from an air/water heat exchanging contact body located within a cooling tower and disposed above the collection system.
In a conventional cooling tower it is well known to employ a stream of air to cool a liquid, such as water, by contacting the air and liquid in a heat exchanging body located within the cooling tower. Such cooling towers are usually provided with a system for collecting the water falling from the heat exchange contact body.
Conventional liquid collection systems may include a tray or pond which is provided at the base of the tower and into which the water from the contact body falls. Because the heat exchange contact body is usually elevated well above ground level, the water may produce a considerable noise when it impacts the tray or collection pond. Furthermore, a large amount of energy is required to recycle the collected water by pumping it back to a water distribution system disposed above the heat exchange contact body.
The use of intermediate level collection systems have been suggested to reduce the noise and the cost of energy. For example, French Pat. No. 876,525 of Aug. 3, 1942 to Hamon, discloses liquid receiving devices which are positioned immediately below a gas/liquid heat exchanging contact body. The liquid receiving devices include a wall inclined from the vertical and a trough extending along the lower edge of the wall. The devices are arranged in parallel and overhang each other to prevent the liquid from falling from the contact body directly to the base of the cooling tower.
In U.S. Pat. No. 4,215,080, issued July 29, 1980 to Ribier et al., (hereinafter usually the "-080 patent") the patentees describe what they consider to be several disadvantages of the receiving devices disclosed in French Pat. No. 876,525. The specification of the -080 patent contends that liquid droplets which strike against the inclined walls disclosed in French Pat. No. 876,525 may burst upon contact with the walls and produce excessive noise. Also, the droplets splashing on the inclined walls may be deflected laterally beyond the troughs which extend along the lower edges of the walls. Thus, the troughs do not collect all of the water falling onto the inclined walls and the water which splashes from the walls may fall to the collection tray at the base of the cooling tower, creating a further noise problem.
An anti-splash device is disclosed in the -080 patent and is said to overcome some of the disadvantages of the collection devices disclosed in the French Pat. No. 876,525. The -080 patent describes the anti-splash device disclosed in it as being disposed above an inclined wall used for collecting a liquid gravitating from a contact or heat exchange body. The anti-splash device includes a panel for trapping the liquid splashes and it is formed by partitioned walls defining passages which are open at the upper and lower ends and closed in the direction of the greatest slope of the inclined wall. The device is said to be designed so that water gravitating from the contact body can pass through the passages onto the inclined wall, but any water droplets splashing from the wall are blocked by the partition walls of the panel.
The anti-splash device of the -080 patent separate panel disposed above each inclined wall of the system. To accommodate the anti-splash devices, it may be necessary in some applications to increase the separation between the inclined walls of the collection system if the inclined walls are to remain overlapping. This in turn may increase the vertical height of the collection system.